I'm fascinated with the Pure Stock Drags (even though my car doesn't fit their format) so I've been toying with the idea of building a stock "sounding/looking" 351w. I'm starting with a '69 2bbl motor, although I do have a '69 4bbl cast intake. Here's the other stuff on my mind; ported C9OE or DOOE heads and exhaust manifolds forged pistons, probably around 10:1 balanced bottom end roller cam conversion(size not yet determined, any help? I want it to sound relatively stock) roller rockers-I've heard that you can stagger them one ratio on the exhaust, one on the intake, does this help? Autolite 4100 1.12 carb Pertronix in the dizzy The trans will be a c4 w/ 3000 stall, the rear is an 8" w/3.55 gears. This combo will go in my '72 Comet. Weight w/driver should be around 3100 lbs. What kind of times should this combo turn(1/8 mile)? I would like to see low 8s-high 7s which means I'll need to coax about 320-380 hp out of it, does that sound about right? Open to comments/suggestions, thanks.
Well the crank and rods will take the HP you plan to make. I would upgrade the rod bolts and stud the mains. As for pistons/compression ratio thats up to what the rules will allow. The D00E heads should be good as well. Cam choice is going to be tough since it has to be a stock grind. Do some research and find out what the biggest cam was that ford offered off the showroom floor. 69/70 mach ones had pretty healthy 351Ws in em.I would start there... Stay with that short deck 69' 351 though,good block to make power/compression with.Good luck!!! Do blueprint the parts...It takes every bit of it to be competitive in pure stock.
I'm not going to be able to compete in those races( cars must have come with a 4bbl and dual exhaust to be allowed in), I would just like to do a build where everything looks/sounds stock. That's why I'm thinking about the roller cam conversion, roller rockers, a good set of lightweight pistons and balancing. Other than those parts, most everything else will be old FoMoCo stuff. I may be going up against a brick wall with this idea, but I would like to try to go as fast as possible with an engine that sounds/looks like it was plucked from an old LTD and thrown in. At least if it's slow I can just say "hey, it's a stock motor out of a LTD!
I'm thinking if you want it to look stock and sound stock, yet put out lots of ponies ... sneaky like ... then displacement is your answer ... stroke it.
Thought about that but.... A friend has a '79 fox body w/a 351w. He stroked it to a 393, but still kept the ported '70 heads. It ran exactly the same, the heads probably are holding it back as they're probably barely adequate for a 351. So I figure money would be better spent either in freeing up a little hp/friction in the motor or throughout the car.
Cool. Didn't know how far you were going with this, and I was't really saying only stroke it, just that stroking it is "undetectable" added power I am surprised your friend saw no increase with the extra cubes.
I was thinking the same thing. With my GTO I swapped out my 400 for a 455. I re-used the cam and top-end from the 400 on the 455 and all else in the car was the same with the exception of the interior. I put it all back in and it still went from a best of 12.77 to 12.35 and then with a carb change it dipped into the 11.80's.
You're right....they won't feed 393" worth a damn. About the biggest valve you can get into those heads is a 1.94/1.55 and then you're shrouding the chambers. Another alternative is to use the Dart/World Products iron heads that come with 2.05/1.60 valves. These can be easily disguised as stock-style heads with a little work. Then you can easily go 393" and use 2.08" intakes and a 1.60" exhaust valve. At that point your limiting factor is the intake and carb. If you keep the stock heads you can go 1.90" intake and 1.55" exhaust with the stock stroke & rod length. You are going to need some very extensive (and careful) porting to make any decent power. Pushrod sleeves, aero-cut valve guides, undercut stem valves, ultra-light valves, etc. If compression is not a concern then I'd put a dome piston in it and get as much as possible. Again, this is going to depend on your choice of fuel. Most of the "Stock Appearing" guys run a much higher octane fuel for this very reason. I'd also run the lightest rod and piston you can afford. Think of this build as a serious Stock Eliminator build with ported heads. Builds like this are always interesting and great engineering games. You can take them to the extreme with special coatings, cut down cranks, hollow stem valves (or even titanium valves), putty-ported intake manifolds, special carbs, etc. It's a lot of fun.
and then you wanta go faster... I hate that part The only thing that holds these motors back is the heads. You can get it all in there you just can't get it all out.
I like it! And i have to agree with you on the probably wont be competetive but it sure would be neat and different. What about a 302 based motor? Go 331 ported exhaust manifolds and dooe 351 cylinder heads and didnt they make a comet gt with a 4v? Just a thought. I know when i went to a couple national nhra national events i saw some really wicked 289 "stock" cars running low 10"s. I also understand theres a big difference in these and the f.a.s.t. drags but still theres alot of good technology there.
I know of some guys close to where I live, who run that type of class, and they pour muratic acid in their intake manifolds to eat the insides out, so they will flow better.
I've been looking at this thread for a couple of days and will give you my 3 cents. Don't go in this direction unless you want to throw away money. First, a stock 351w with stock type heads (ported/polished/flowed) will cost you just as much as some good AFR/TFR or whatever aluminum heads that will flow 2/3 times more than your expensive cast heads. On any 289/302/351w motor the key to making HP are the heads! Go buy some aluminum heads and paint them the color of the block if you want stealth. Second, if you stay with the parts you listed in your first post you will never reach the 320hp if you have an aftermarket intake and Holley/Edelbrock or sometype of aftermarket carb maybe, but if you are willing to spend more than a new carb would cost for mods...............and even then it won't match the aftermarket carb. No need to spend $400 on forged pistons as they are not needed and how light they are will make no difference if you can't spin the motor over 5,000 and still be making HP.....................with a stock cam you will not. As for the stock exhaust manifolds, remember, the motor is just an "Air Pump", and you can't get air in with a stock cam......................and if you were able to get enough air in, with the stock exhaust you will never be able to get it out..........................so, with the parts you listed in the first post I would be surprised if you could even make 300hp ATC............ (At The Crank). So, as they say cubic inches make cubic Torque, and Torque equates to HP. If you wanted stealth go with a 408ci or 427ci motor and you may get to the 350/400hp level. We used to build "Sleepers" back in the 60's and early 70's, and the cars look bone stock on the outside but were filled with everything including the kitchen sink..............................52 Chevy with a 427 rat motor that would leave black streaks on the road for 1/4 mile with the small/narrow tires and from a 30/40mph roller would make the car go sideways. I had a stock looking 56 chevy 2dr sedan that looked like a restored old car with a full boogy 327, dual fours and roller cam with a 4spd that had a 3spd shifter knob and you could only see one exhaust pipe coming out but the motor put out 415hp on the engine dyno and this was back in 1965. I had headers on the car and they went into stock mufflers where the car would barley run, but when you found someone and put $25 bucks on the line, I would pull what looked like manual chokes and the cutouts would bypass the stock mufflers...................................that was street racing some 45 years ago............................didn't mean to get off subject but I think what you have outlined is a waste of time, money and effort. IMHO
Now I figure if I can build a 350 hp 289 back in 1970 it should be easy to do the same with a 302 or close to 500hp with a 351W today. I used the stock heads and a Shelby hi-rise manifold. I had to turn the engine to 7200 rpm to do it but it is not that difficult to do with factory components. To bring this up to date I have a 365 hp 351W with factory iron heads that I only have to turn to 5500 rpm. You don't NEED aftermarket parts to get hp. You do need to do some work and plan the engine from carb to tail pipe but it can be done.
StrokerMaverick, Yes, when I ran SS back in the early 70's there were a lot of tricks pulled in all the classes. We would put alcohol in the windsheild washer reservoir and direct it into the carb, and some guys used stronger stuff. Acid dipping was good but NHRA Tech got wise, we tried that with our stock intakes in the begining, then they started to allow aftermarket intakes but we still had to use the stock 4brl carb. Some of the bucks up guys dipped the whole car...................your were always trying to stay one step ahead of the tech group. GreaseMonkey, Yes, back when my Maverick was running B/SM it had a 302 with 4spd and was turning in the 10.3's, lauch at 8,500rpm and go through the traps at close to 9,000rpm.........................but the motor had Boss 302 heads and cost upwards of $10k to build and that was in 1979. I have had more than one 289HiPro and I can tell you that in my 64 Comet with stock (blueprinted SS motor) I was in the high 11's with 4spd. They can't touch me now, but it had a set of 69 4brl 351w heads with shim steel head gaskets (that I replace almost every weekend) and some very creative grinding on the crank that took almost 5lbs of material off, not to mention the 302 rods, cheater cam, light weight flywheel and a set of 4:56 gears.........................the motor would spin over 8,500rpm through the traps...........................if you want race in Pure Stock/Stock/SS you need to be willing to spend some serious money................One of the reasons I got out of drag racing some 25 years ago is that I didn't have the money to be close enough to the National Records I was always hopefull of making..................The ole saying goes "There is always somebody out there that makes more HP than you and always someone out their that has more money than you do to be able to go faster than you can afford"....................................So................now I do it for myself and to have as much fun as my money can take me............IMHO
If you want to seem stock and make good power, stroke it and use a mild roller hydraulic cam. I have a 351W stroked to 421 that idles at 800 rpm's and could pass for stock. Since you are planning to change pistons and rods anyway, a sroker kit only costs a little more. Once you have the cubic inches a lot of the other stuff can be added later. Watch ebay for some good aluminum heads and you will really wake it up. That's my two cents. Lee "THE MAV" Richart
